This invention relates to fluid processes and more particularly to a pressure shutoff valve monitoring fluid pressure in a fluid process vessel.
1. Field of the Invention
A fluid process contained by a vessel is continually supplied with fluid at a predetermined pressure regulated by a pressure regulator interposed in the fluid supply line. However, fluid regulators sometimes fail, and usually fail in the open position, thus allowing pressure above the predetermined limit to enter the pressure fluid processing vessel. Even if a second regulator is interposed in tandem in the line leading to the vessel it does not solve the problem for the reason that when one regulator fails a second companion downstream regulator usually also fails, and in the open position.
This invention solves the problem of a failed pressure regulator by a normally open pressure shutoff and relief valve, interposed in the fluid supply line upstream or downstream from a fluid pressure regulator connected with a process vessel. The shutoff valve monitors fluid supply pressure on the downstream side of the fluid pressure regulator, and is biased closed by fluid pressure above a predetermined limit and bypasses the fluid to a suitable line or receptacle.
2. Description of the Prior Art
I do not know of any patents disclosing this feature.